Vehicle brake



1,584,] 1 1 M. w. MccoNKEY 3 Sheets$heet 1 VEHICLE BRAKE Filed May 23, 1925 INVENTOR May 11 1926.

M. W. M CONKEY vEHicLE BRAKE FiledMay 23, 1925 m I5 Sheets-Sheet 2 a INVENTOR May 11 1926 W n a a N m 1 L M m F K w x V I-FD] INVENTOR FIG-5 Patented May 11, 192a UNITED STATES PATENT OFFICE,

MONTGOMERY MGCOIQ'KEY, OF CHICAGO, ILLINOIS, ASSIG'NOR TO IBENDIX'. BRAKE COMPANY, OF CHICAGO, ILLINOIS, A CORPOBAIIONLOF ILLINOIS.

vnmcnn BRAKE,

Application filed May 23, 1925. Serial No. 32,317.

This invention relates to brakes, and is il- 'lustrated as embodied in an automobile, chassis. object of the invention is to provide. a povverfulauxiliary or servo device for applying the brakes, ,which will act without appreciable lag arid which can be accurately controlled tojggive'fany desired pressure on the brakes. In onejve'ry effective arrange ment, a PIStrOII OT', other power device con" nected to the briikes is acted on by opposed balanced forces, for example by fluid at the same pressure onboth sides'ofgthe piston,

and the controlling means acts to unbalance the forces, as by exhausting the fluid on i5 by power.

' one side of the piston, to apply the brakes vention relate to arrangements for graduating the control, preferably so that the power applied to the brakes is a predetermined multiple of the force exerted by the driver.

Other objects and features of the invention, includin a novel arrangement for delivering a re uced. uniform fluid pressure to the; fuel tank from the brake mechanism, for the purpose of feeding the fuel, and other new combinations of parts and desir able particular constructions, will be ap parent from, the following description of one illustrative embodiment shown in the accompanying drawings, in Which:

Figure Lis a diagrammatic top plan view of an automobile chassis embodying the invention; v

Figure 2 is a vertical section through the servo on the line 2-2 of Figure l;

Figure 3 is a partial side elevation of the servo, looking in the direction of the arrow 3, Figure 1;

Figure 4 is a vertical section through the servo on the line 44, Figure 1;

Figure 5 is a transverse vertical section through the servo on the line5,5, Figure 1;

Figure 6 is a vertical section through the top of the filler spout of the fuel tank.

the road wheels 16, may be operated from a rockshaft 20 by a linkage 22. .'The fuel Important features of the in-- tank is shownat 24, and the engine at-26. The shaft 20 may be rocked to apply the brakes 18 by depressing a pedal 28 or the like .shownas operating a link 30 having an over-running connection with an arm' on shaft 20-. The shaft is ordinarily, however, operated by a link-32 from a piston 34 (Figure 4) in a cylinder 36 in a power'or servo device 38.

The power device 38 contains two fluid reservoirs 40 and 42 communicating respectively by ports 44 and 46 with opposite ends of cylinder 36'. Ordinarily the cylinder 36 and-the bottom'of the two reservoirs will be filled with oilor other liquid, although this is not essential in the broader aspects 54 (Figure 3) on alink 56 from the brake pedal 28 against the resistance of a spring 58, in the position shown in Figure 4, in which reservoirs 40 and 42 are in communication with each other-and both are in communication with conduit 48.- Thus normally the pressure on opposite sides of piston 34 is the same. When pedal 28 is depressed, spring 58 rocks arm 60 of valve 52 against a stop 62, cutting off communication between the two reservoirs 40 and 42 and between both reservoirs and conduit 48.

The pressure in the two reservoirs is con trolled from pedal 28 or its equivalent by means such as is shown in one embodiment in Figure 2. In the illustrated arrangement, alink 64 operated by the pedal has a head 66 engaging and compressing a spring 68 In the arrangement selected for illustra against a diaphragm 70, shown as one of the corrugated metal bellows known commercially as a sylphon tube. Diaphragm 7 0 is connected totwo exhaust valves 72 and 74, one in each of the reservoirs 40 and 42, by means shown diagrammatically as wires 76, so that movement of the diaphragm to the right will place reservoir in the communication with the atmosphere, while movement to the left will place reservoir 42 in communication with the atmosphere. In a central neutral position of the diaphragm, both exare normally at a. hi h pressure. Depressionhrst allows spring 58 to of the brake pedal fclose valve 52. As spring 68 is compressed, valve 72 is opened, the pressure in reservoir 40 is reduced, and the difference in pressure between reservoirs 40 and 42 forces piston 34 tothe left (Figure 4) toapply the brakes. As soon as the greater pressure in reservoir 42 balances the pressure on spring 68, diaphragm 70 is forced back to its neutral position against the resistance of spring 68, and the brakes are held on with a pressure which is a predetermined multiple of the pressure on the brake pedal.

If now more pressure is exerted on the brake pedal, the same operation is repeated, and the parts again balance with a corresponding greater pressure on the brakes. If the pressure on the pedal is relieved, the excess pressure in reservoir 42 forces the diaphragm to the left to open valve 7 4, until the excess pressure in reservoir 42 again ]ust balances the pressure on' spring 68. hen

i the pedal is entirely released, equal pressure in the two reservoirs is immediately re-established by the return of valve 52 to the position shown in Figure 4.

' i One feature of the invention relates to maintaining in the/tank 24 a low fuel-feeding pressure from the high pressure main tained in the brake-applying, means. The tank and the servo are connected by a con-' duit 90 opening from a small reservoir 92- in a novel pressure-reducing valve 94 threaded into one end of reservoir 42. The valve proper is shown diagrammatically at 96, and is connected by a rigid link 98 to a second sylphon or other diaphragm 100 constantly compressed by a spring 102 held by an adjustable threaded p-lug'104, By turning up plug 104 more or less, a greater or less constant pressure is exerted on diaphragm 100 tending to open valve 96 to admit compressed gas to tank 24. Vhen the pressure in reservoir 92 just balances the pressure of spring 102, valve 96 is automatically closed.

Preferably conduit 90 0pens in the filler spout 106 of the fuel tank, and has a check valve 108 normally held open by engagement with the tiller cap 110. lVhen cap 110 is removed'to refill'the tank,'valve 108 prevents emptying reservoir 42 of its compressed gas. VVhen'cap 110 is replaced,'the desired 1 low fuel-feeding pressure is automatically .reestablished in the fuel tank.

While one illustrative embodiment of the invention has been described in detail, it is not'my intention to limit its scope to that particular embodiment, or otherwise than by the termsof the appended claims.

I claim:

1. A vehicle having, in combination, brakes, means for operating the brakes including a power-operated member, two res ervoirs for fluid at other than atmospheric pressure and acting inopposite directions on said member, the pressures in said reservoirs normallybeing balanced, and means for placing one reservoir in communication with the atmosphere to apply the brakes and forpla'cing the other reservoir incommunication with the atmosphere to relieve the pressure on the brakes.

2. A vehicle having, in combination, brakes, means for operating the brakes including a power-operated member, two reservoirs for fluid at other than atmospheric pressure and acting in opposite directions on said member, normally open means for connecting the reservoirs to balance the pressure, means for. simultaneously disconnecting the reservoirs and for placing one reservoir in communication with the atmosphere to apply the brakes, and an operating sures in said reservoirs, and means for selectively exhausting the, reservdirs to the atmosphere to apply and release the brakes.

. 4, A vehicle having, in combination, brakes, means for operating the brakes including a power-operated member, two fluid reservoirs containing fluid acting on opposite SlClGSs of said member, means for compressing fluid at substantially equalpres= sures in said reservoirs, and means .for ex hausting one or the other reservoir to the atmosphere to establish a graduated difference in the pressures acting in opposite directions on said member" brakes.

5'. A vehicle having, 9 in combination, brakes, means for operating the brakes including a power-operated member, two fluid reservoirs containing fluid acting on opposite sides of said member, means for establishing equal pressures other than atmosto apply the the forces acting on said member, a. valve pressure-responsive means for opening and closing the valve to apply the brakes with a graduated pressure determined by the driven. p

-'6. A vehicle having, in combination, brakes, means for operating the brakes includingf'a power-operated member, two. fluid reservoirs containing-fluid acting on'oppositesides of said member, means for establishing equal pressures other than atmos-' phe'rio pressure 1n the reservoirs to'balance the' foroes acting'on said member, a valvefor placing each reservoir in communication with the atmosphere, and driver-controlled means for opening one valve to apply the brakes and for opening the-other valve'to release the brakes.

7.'-A vehicle having, in combination, brakes, means for operating the brakes including a power-operated'member, two fluid reservoirs containing fluid acting on opposite sides of said member, means for establishing equal pressures other than atmospheric pressure in the reservoirs to balance the forces acting on said member, a valve for placing each reservoir in communication with the atmosphere, a driver-operated controlling member, means operated by movement of the controlling member in one direc' tion to' open one of the valves, means operated by movement of the controlling member in the other direction to openithe other valve,and means for closing the valves.

8, A. vehicle having, 111 combination,

I brakes, means for operating the brakes ineluding a power-operated member, two fluid reservoirs containing fluid acting on opposite sides of said member, means for establishing equal pressures other than atmospheric pressure in the reservoirsto balance the forces acting on said member, a valve for placing each reservoir in communication with theatmosphere, a driver-operated controlling member, means operated by move ment of the controlling member in one di-' rection to open one of the valves, means for automatically closing said valve after the pressure in the reservoir has changed by an amount determined by the extentof movement of the controlling member, means operated by movement of the controlling member in the other direction to open the other valve, and means for closing the said other valve when the pressures in the reservoirs are again at a differential determined by the position of the controlling member.

9. A vehicle having, in combination,

brakes, means for operating the brakesincluding a power-operated member, two fluid reservoirs. containing fluid acting on opposite sides of said member, means for es tablis hing equal pressures other than atmosQ with the atmosphere, a driver-operated controlling member, means operated by move ment of the controlling member in one direction' to open one of the valves, means operated by movement of the controlling memher in the other direction to open the other valve, means for closing the valves, and meansautomatically' operated on movement of the controlling member to initial position to place the two reservoirs in communication with each other to balance the pressure in the reservoirs.

10."A vehicle having, in combination, brakes, means for operating the brakes including a power-operated member, two fluid reservoirs containing fluid acting on said member in opposite directions, means for establishing equal pressures other than atmospheric pressure in said reservoirs to balance the forces actingon said member, a spring, valve means operated by distortion of the spring to differentiate the pressures in the two-reservoirs in an amount determined by distortion of the spring, and means for distorting'the spring to cause said member to apply the brakes. v

11. A vehicle having, in combination, brakes, means for operating the brakes including a power-operated member, two

fluid reservoirs containing fluid acting on of the spring to differentiate the pressure in the two reservoirs in an amount proportional to the force acting on the spring, and means for distorting the spring to cause said member to apply the brakes.

12. A vehicle having, in combination, brakes, means for operating the brakes including a power-operated member, two fluid reservoirs containg fluid acting on said member in opposite directions, means for establishing equal pressures other than atmospheric pressure in said reservoirs to balance. the forces acting on said member, a spring, valve means operated by distort-ion of thespring to differentiate the pressures in the two reservoirs in an amount proportional to the force acting on the spring, and a driver-operated part for distorting the spring more or less to apply the brakes with a graduated pressure in proportion to the force exerted'by the driver.

18. A vehicle having, in combination, brakes, means for operating the brakes including a power-operated member, two fluid reservoirs containing fluid acting on said member in opposite directions, means for establishing equal pressures other than atmospheric pressure in said reservoirs to balance the-force's acting onsaidmember, a spring, valve means operated by distortion of thespring to diiierentiate the pressures .in the two reservoirs in an amount proportional to the force acting on the spring, a driver-operated part for distorting the spring more or less to apply the brakes with a graduatedpressure "in proportion to the force'exerted by the driver, and auxiliary connections from said part ior applying'the brakes manually in case ofi'insuiiicient fluid pressure. I

14. f vehicle having, in combination, brakes, means for operating the brakes including a power-operated member, two fluid reservoirs containing fluid acting on said member in opposite directions, means for establishing equal pressures other than atmospheric pressure in said reservoirs to bal ance the forces acting on said member, a pressure-responsive device communicating on opposite sides with the two reservoirs, a valve for each reservoir, the valves being operated by said pressure-responsive device and one valve being operated by increase of pressure in one direction on saiddevice-and the other valve being operated by increase of pressure thereon in the opposite direction, and means for increasing the pressure on said device in one direction more or less to operate the corresponding valve to place one reservoir in communication with the atmosphere to differentiate the pressure on opposite sides of the power-operated member to: apply the brakes.

15. A vehicle having, in combination, brakes, means for operating the brakes including a power operated-member, two fluid reservoirs containing fluid acting on said member inop'posite directions, means for establishing equal pressures other'thanatmospheric pressure in said reservoirs to balance the iiorces acting onsaid member, a

pressure-responsive device communicating on opposite sides with the two reservoirs, a valve for each reservoir, the valves being operated by said pressure-responsive device and one .valve bein operated by increase of ressure in one irectionon said device an the other valve being operated by in-' crease of pressure thereonin the opposite direction, and means for yieldingly increas ing the pressure on said device in one direction more or less to "operate the corresponding valve to place one reservoir in communication with the atmosphere to differentiate the pressure on opposite sides of the power-operated member to apply the brakes, said pressure-responsive device automatically closing the valve again when the pressure onthe brakes is a predetermined multiple of the increase in! ressure on said device. 16. power evice comprising, combination, apower piston, two fluid reservoirs communicating with opposite sides of the piston and normally containing fluid at balanced pressures, a valve for placing each reservoir in communication with the atmosphere, a pressure-responsive device besides with the two reservoirs, connections from said device to the two valves, andmeans yieldingly acting on the pressure-responsive device to. cause one valveto be opened thereby, to change the pressure onone side of the piston in an amount determined by the pressure of said'means on the act on the pressure-responsive device, and

controlling means includingfa plunger for compressing the spring against said device. 18. A power device comprising, in combination, a piston and cylinder, two reservoirs communicating with the cylinder on opposite sides ofthe piston, a liquid filling the cylinder and submerging the piston and tween and in communication on oppositerising part way, into the reservoirs, means a for supplying compressed gas at balanced pressuresto the two reservoirs, and means for effecting the graduated exhaust of the gas from one reservoir to cause a difference in the pressures" acting in opposite directions on the piston.

19. A power device comprising, in combination, a piston and cylinder, two reservoirscommunicating with the cylinder on opposite sides of the piston, a liquid filling the cylinder and'submerging the piston and rising part way into the reservolrs, means for supplying compressed gas at balanced pressures to the two reservoirs, an exhaust valve for each reservolr, and means including a controlling member for controlling the two valves to establish and maintain a difierence 1n pressure in the two reservoirs and for reacting on the controlling member in proportion to said difierence in pressure. In testimony whereof I have hereunto signed my'name.

MONTGOMERY w. MGCONKEY. 

